INTERSECT equivalent in MySQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to select common names from two tables using INNER JOIN.

MySQL

SELECT a.name FROM table1 a INNER JOIN table2 b ON a.[1] = b.name;

Drag options to blanks, or click blank then click option'

Aid

Bvalue

Cname

Ddate

Attempts:

3 left

💡 Hint

Common Mistakes

Using different column names in the ON clause.

Using a column that does not exist in one of the tables.

The INNER JOIN matches rows where the 'name' column is the same in both tables, simulating INTERSECT.

2fill in blank

medium

Complete the code to find common ids using EXISTS to simulate INTERSECT.

MySQL

SELECT id FROM table1 t1 WHERE EXISTS (SELECT 1 FROM table2 t2 WHERE t2.[1] = t1.id);

Drag options to blanks, or click blank then click option'

Aid

Bvalue

Cname

Ddate

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong column in the subquery.

Forgetting to correlate the subquery with the outer query.

The EXISTS clause checks if the id from table1 exists in table2, returning common ids.

3fill in blank

hard

Fix the error in the query to simulate INTERSECT using IN clause.

MySQL

SELECT name FROM table1 WHERE name [1] (SELECT name FROM table2);

Drag options to blanks, or click blank then click option'

AIN

BNOT IN

C=

DLIKE

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' which compares only one value, not a list.

Using NOT IN which returns non-matching rows.

The IN operator checks if 'name' from table1 exists in the list of names from table2, simulating INTERSECT.

4fill in blank

hard

Fill both blanks to simulate INTERSECT using INNER JOIN with aliasing.

MySQL

SELECT [1].id FROM [2] a INNER JOIN table2 b ON a.id = b.id;

Drag options to blanks, or click blank then click option'

Aa

Btable1

Ctable_one

DtableA

Attempts:

3 left

💡 Hint

Common Mistakes

Using different aliases in SELECT and FROM.

Using a wrong table name.

The alias 'a' is used to refer to 'table1' in the SELECT and FROM clauses for the join.

5fill in blank

hard

Fill all three blanks to simulate INTERSECT using EXISTS with correct table aliases and column.

MySQL

SELECT [1].name FROM [2] [1] WHERE EXISTS (SELECT 1 FROM [3] WHERE [3].name = [1].name);

Drag options to blanks, or click blank then click option'

At1

Btable1

Ctable2

Dt2

Attempts:

3 left

💡 Hint

Common Mistakes

Using inconsistent aliases.

Mixing up table names in the subquery.

Alias 't1' is used for 'table1' in FROM and SELECT. The EXISTS subquery checks 'table2' for matching names.